Hibe desteği NHLBI HL080532, NHLBI HL073449 NCRR RR16453 ve Hibe Yardım Ödülü (RVS) AHA Milli dahil etmiştir. Mesafe Ders Tasarım ve Danışmanlık (DCDC) grubu, dcdcgroup.org, video üretimi ile yardım için özel bir teşekkür ve DCDC kurdu Eğitim Bursu No P336C050047 US Department of uzatılır.

1. Mikro stok hazırlama <ol><li> 10 ml PBS 1 gr glukoz 200 mg 1,2-dipalmitoyl-sn Glycéro-3-fosfatidilkolin ve 50 mg 1,2 dipalmitoyl-sn-Glycéro-3-phosphatidylethanolamine karıştırın. </li><li> Pipet her 5 dakikada bir karıştırma, karışım kaynar su banyosunda 20-30 dakika ısıtın. </li><li> Çözüm, 6 aya kadar 4 ° C saklanabilir. </li></ol> 2. Mikro Hazırlık <ol><li> 40 mikrokabarcık hazırlanan stok solüsyonu ve inkübe ° C 15 dakika boyunca 250 ul çekin. </li><li> Sonra önceden ısıtılmış mikrokabarcık çözüm 50 ul gliserol içeren 1,5 mL mikrotüp aktarılır. </li><li> Bir ifade ilgi gen (bu örnekte 4mg/ml optimal bir konsantrasyon ile Qiagen Endotoksin ücretsiz MegaPrep kiti, Qiagen, Germantown, MD, saflaştırılmış) inşa kodlayan plazmid DNA saflaştırılmış 1-2 mg. 500 ul nihai hacmi 2.4) Fosfat-tamponlu salin eklenir. Endotoksin ücretsiz Qiagen maxipreps kısırlık sağlamak için de steril PBS olarak kullanılır. </li><li> Mikrotüp hava, sonra Octafluoropropane gaz ile değiştirilir. </li><li> Mikrotüp sonra, 20 saniye boyunca bir diş amalgamator kuvvetlice çalkalanır. </li><li> Mikro kabarcık bağlı değildir subnatant içeren kalıntı DNA ve tampon daha sonra dikkatlice çıkarılır ve mikrokabarcık katman unattached DNA kaldırmak için steril PBS ile üç defa yıkanır ve her yıkama döngüsü arasında buz konur. Biz genellikle% 30-40 bağlayıcı bir verimlilik elde edin. Tüm reaktifler steril ve bakım kontaminasyonu en aza indirmek için yapılır. </li><li> Plazmid DNA bağlı mikro kabarcık, iki saat sonra, kullanılıncaya kadar buz üzerinde yukarı yerleştirilir. </li><li> Karıştırma ve PBS yıkar sonra mikrotüp kaldırılır subnatant, bu çözümün kullanılarak 260nm dalga boyunda optik yoğunluk ölçüm bağlanmamış DNA konsantrasyonu, ve aynı şekilde bilinen ilk konsantrasyon dayalı bağlı miktarını belirlemek için kullanılır. Bir spektrofotometre. </li></ol> 3. Cihazları Kalibrasyonu <ol><li> İlk kullanımdan önce, 1 MHz kavitasyon transdüser uygun mekanik indeksi ve darbe tekrarlama sağlamak için kalibre edilmesi gerekir. Bir dalgıç 1 MHz, 13mm, odaklanmamış transdüser bir güç amplifikatörü ile 20 MHz Fonksiyon / Keyfi Dalga Şekli Jeneratörü bağlı. </li><li> Dönüştürücü bir şarj amplifikatör ile 500 MHz osiloskop bağlı olmuştur hidrofon, doğrudan doğruya hedef, su dolu bir plastik kap konur. </li><li> Dalga, frekans, genlik, patlama döngüsü ve amplifikatör gücü, uygun görev döngüsü ve mikro kabarcık cavitate optimal mekanik indeksi elde etmek için modifiye edilebilir. Bu deneme için, 1 MHz&#39;de ~ 1.3 eşdeğer mekanik bir dizin sistemi kalibre var. </li></ol> 4. Mikro Teslimat &amp; UTMD <ol><li> Mikrokabarcık teslimat ve UTMD önce C57BL / 6 fareler IP enjeksiyon yoluyla 5mg/kg ketamin ve ksilizin 100mg/kg ile anestezi edildi. </li><li> Mikro teslim veya kuyruk ven kateterizasyonu ile kalbin sol ventrikül içine direkt enjeksiyon yoluyla intravenöz verildi. Doğrudan kalp enjeksiyon için 100 plazmid DNA yüklü mikrokabarcık çözüm ul hacmi, kalbin sol ventrikül içine ultrasonik görüş altında ön 4. interkostal eklenen bir 30 gauge iğne ile enjekte edilir . </li><li> Sol interventriküler enjeksiyon kaynaklanan mikrokabarcık çözüm bolus Vevo 2100 Görüntüleme Sistemi Visual Sonics &#39;fare toraks VisualSonics kullanarak uzun eksen üzerinde sabit bir konumda yerleştirilmiş 38 MHz yüksek frekanslı ultrason probu&#39; kullanılarak görüntülenmiştir. Bu enjeksiyonlar için mümkün olan en steril ortamda sigortalanması Tüm şırınga ve iğneler, steril. </li><li> Enjeksiyonu takiben hemen, mikrokabarcık imha ~ 5 dakika ikinci bir küçük boyutlu düşük frekanslı 1.0 MHz transduser kullanılarak, istenilen organ üzerindeki doğrudan düzenlenen bu bölgede imha hedef için yapılır. Bu örnekte, ultrason mekanik yaklaşık 1,3-1,5 indeksi eşdeğeri, ve her 20 döngüleri için 100 ms darbe tekrarlama süresi, darbe tekrarlama frekansı 1.0 MHz karaciğer verildi. Alternatif olarak, darbe ultrason 3 kare, her 4-6 kalp döngüleri bir patlama (bu denemede gösterilmez) fare EKG gated olabilir. Biz ultrason patlamaları arasında kabarcıkları ile dolum kapiller yatak izin protokolleri ile transfeksiyon daha fazla verim almak. </li></ol> 5. Alternatif Dağıtım Yöntemi Prosedürün karmaşıklığı nedeniyle interventriküler enjeksiyon vurgulamak için seçti, ancak mikro kabarcık uzun süreli infüzyon, bir kuyruk ven gibi birçok örnekleri,Enjeksiyon tercih edilen yöntemdir. Mikrokabarcık teslim kuyruk ven yöntemi için, fare, aynı şekilde anestezi. 27 iğne / kuyruk ven kateteri, plazmid DNA bağlı mikro kabarcık içeren bir şırınga bağlıdır. Kuyruk fare kuyruğu boyunca ya sağ ya da sol lateral damarları distal ven kateteri yerleştirilir. Mikro kabarcık içeren şırınga zaman önceden belirlenmiş bir süre içinde çözüm bir üniforma önceden ayarlanmış otomatik olarak yöneten bir infüzyon pompası yerleştirilir. Biz genellikle 3ml/hour bir oran 200-300μl demlenmeye. Hayvan kullanımı Bütün hayvanlar iyi hayvan uygulama ile ilgili ulusal ve / veya yerel hayvan refahı organları tarafından tanımlandığı şekliyle uygun olarak ele alındı ​​ve tüm hayvan çalışmaları (Hawaii Kurumsal Hayvan Bakım ve Kullanım Kurulu Üniversitesi, onay numarası 07-100 uygun komitesi tarafından kabul edildi -3). Uygun anestezi (ketamin / zylazine) kullanılan ve analjezikler (bupivakain ve Buprenorfin) ama gerekli değil, mevcut idi. 6. Temsilcisi Sonuçlar: UTMD aracılı plazmid DNA teslim etkinliği, yapı gibi kodlanmış genler bağlı yöntemlerden çeşitli aracılığıyla değerlendirilir, ancak bunlarla sınırlı değildir; B-gal ex vivo boyama, in vivo görüntüleme, ve / veya lusiferaz İmmunohistolojik. Özellikle, in vivo biyoparlaklık görüntüleme bir seri bir plazmid kodlama bioluminescent muhabiri geni (lusiferaz) ile transfekte farelerde gen ekspresyonu varlığı ve süresi izlemenize olanak sağlar. Vivo Görüntüleme Sistemi (IVIS) Xenogen (Kaliper Yaşam Bilimleri, Hopkinton, MA) bioluminescent görüntüleme için kullanılır. Görüntüler genellikle tüm fareler UTMD aracılı transfeksiyon sonra ilk gün alınır ve bioluminescent gen ekspresyonu artık görsel sistem (Şekil 1) saptanabilir kadar her üç dört gün tekrarlanır. Bioluminescent görüntüleme için fareler hazırlamak için, fare ilk prob D-luciferase (Kaliper Yaşam Bilimleri) ve daha sonra anestezi ~ 3 dakika sonra lusiferaz muhabiri bir IP enjeksiyon almak. D-luciferase substrat Biodistribution hayvan IVIS görüntüleme odasında yerleştirilir ve bir tam vücut imajı taraması çekilmeden önce ~ 10 dakika boyunca devam etmesine izin verilir. Satın alma sırasında, ateşböceği lusiferaz / D-luciferase fotokimyasal reaksiyon yayılan fotonlar ölçülür. Şekil 1 UTMD aşağıdaki karaciğer benzer IVIS bioluminescent görüntüleme göstermektedir ve Şekil 2 lusiferaz bir anti-primer antikor (Sigma-Aldrich) ve AlexFluor-568 konjuge sekonder antikor (Invitrogen) kullanarak transfekte karaciğer Epifloresans (100X) görüntü . UTMD aracılı karaciğer transfeksiyon endotel hücreleri sadece etkiledi görmek için açıktır, ama hepatocyes yanı. <img src="/files/ftp_upload/2963/2963fig1.jpg" alt="Şekil 1" /> Şekil 1 Xenogen / IVIS kardiyak görüntüleme tedavi edilen farelerde UTMD (A) Negatif Kontrol Fare:. Plazmid + PBS kardiyak yönettiği UTMD takip, (B) Tedavi Fare: Plazmid + kalp tarafından takip Mikrobaloncuklar UTMD yönettiği ve (C) Tedavi Fare karaciğer tarafından takip Plazmid + Mikrobaloncuklar UTMD yönetti. <img src="/files/ftp_upload/2963/2963fig2.jpg" alt="Şekil 2" /> Şekil 2 hiçbir UTMD karaciğer UTMD İmmünohistokimya (anti-lusiferaz kırmızı) (A) Plazmid ve (B) UTMD Plazmid. Konfokal görüntü (100X); çekirdekleri DAPI lekeli mavi.

<ol>
	<li>Bekeredjian, R., Chen, S., Frenkel, P. A., Grayburn, P. A., Shohet, R. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrasound-targeted+microbubble+destruction+can+repeatedly+direct+highly+specific+plasmid+expression+to+the+heart.">Ultrasound-targeted microbubble destruction can repeatedly direct highly specific plasmid expression to the heart.</a> Circulation. 108, 1022-1026 (2003).</li><li>Bekeredjian, R., Katus, H. A., Kuecherer, H. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Therapeutic+use+of+ultrasound+targeted+microbubble+destruction:+a+review+of+non-cardiac+applications.">Therapeutic use of ultrasound targeted microbubble destruction: a review of non-cardiac applications.</a> Ultraschall Med. 27, 134-140 (2006).</li><li>Chen, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regeneration+of+pancreatic+islets+in+vivo+by+ultrasound-targeted+gene+therapy.">Regeneration of pancreatic islets in vivo by ultrasound-targeted gene therapy.</a> Gene Ther. 17, 1411-1420 (2010).</li><li>Miao, C. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrasound+enhances+gene+delivery+of+human+factor+IX+plasmid.">Ultrasound enhances gene delivery of human factor IX plasmid.</a> Hum Gene Ther. 16, 893-905 (2005).</li><li>Shimoda, M., Chen, S., Noguchi, H., Matsumoto, S., Grayburn, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+non-viral+gene+delivery+of+human+vascular+endothelial+growth+factor+improves+revascularisation+and+restoration+of+euglycaemia+after+human+islet+transplantation+into+mouse+liver.">In vivo non-viral gene delivery of human vascular endothelial growth factor improves revascularisation and restoration of euglycaemia after human islet transplantation into mouse liver.</a> Diabetologia. 53, 1669-1679 (2010).</li><li>Shohet, R. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Echocardiographic+destruction+of+albumin+microbubbles+directs+gene+delivery+to+the+myocardium.">Echocardiographic destruction of albumin microbubbles directs gene delivery to the myocardium.</a> Circulation. 101, 2554-2556 (2000).</li><li>Sirsi, S., Borden, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbubble+Compositions,+Properties+and+Biomedical+Applications.">Microbubble Compositions, Properties and Biomedical Applications.</a> Bubble Sci Eng Technol. 1, 3-17 (2009).</li><li>Li, H. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrasound-targeted+microbubble+destruction+enhances+AAV-mediated+gene+transfection+in+human+RPE+cells+in+vitro+and+rat+retina+in+vivo.">Ultrasound-targeted microbubble destruction enhances AAV-mediated gene transfection in human RPE cells in vitro and rat retina in vivo.</a> Gene Ther. 16, 1146-1153 (2009).</li><li>Lindner, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbubbles+in+medical+imaging:+current+applications+and+future+directions.">Microbubbles in medical imaging: current applications and future directions.</a> Nat Rev Drug Discov. 3, 527-532 (2004).</li><li>Newman, C. M., Bettinger, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+therapy+progress+and+prospects:+ultrasound+for+gene+transfer.">Gene therapy progress and prospects: ultrasound for gene transfer.</a> Gene Ther. 14, 465-475 (2007).</li><li>Vancraeynest, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Myocardial+injury+induced+by+ultrasound-targeted+microbubble+destruction:+evidence+for+the+contribution+of+myocardial+ischemia.">Myocardial injury induced by ultrasound-targeted microbubble destruction: evidence for the contribution of myocardial ischemia.</a> Ultrasound Med Biol. 35, 672-679 (2009).</li></ol>

UTMD gen teslimat için yeni bir yaklaşımı temsil ediyor. Bir teknoloji platformu olarak, doku özgüllüğü yüksek derecede istenilen biyoaktif moleküllerin sayısız sunmak için birçok potansiyel gen tedavisi stratejileri ile kombine edilebilir. Tekniğin ana biyolojik sınırlama transfeksiyon en düşük verim. Bir başka önemli husus, belirgin, kemik ya da hava müdahale ederek azalmış olabilir ultrason, hedef organ erişilebilirlik. Bu teknik, doku hasarı 11 ve verimliliği artırmak sınır...

<table border="1">
	<tbody>
		<tr>
			<th>Name of the reagent/equipment</th>
			<th>Company</th>
			<th>Catalogue number</th>
			<th>Comments</th>
		</tr>
		<tr>
			<td>1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine</td>
			<td>Sigma-Aldrich</td>
			<td>P-5911</td>
			<td>component of the microbubble lipid shell</td>
		</tr>
		<tr>
			<td>1,2-dipalmitoyl-sn-glycero-3-phosphatidylethanolamine</td>
			<td>Sigma-Aldrich</td>
			<td>P-3275</td>
			<td>component of the microbubble lipid shell</td>
		</tr>
		<tr>
			<td>glucose</td>
			<td>Sigma-Aldrich</td>
			<td>G5400</td>
			<td>thought to stabilize the microbubbles</td>
		</tr>
		<tr>
			<td>phosphate-buffered saline</td>
			<td>Sigma-Aldrich</td>
			<td>P5368</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>glycerol</td>
			<td>Sigma-Aldrich</td>
			<td>G5516</td>
			<td>believed to prevent microbubbles from coalescing</td>
		</tr>
		<tr>
			<td>Octafluoropropane gas</td>
			<td>AirGas</td>
			<td>N/A</td>
			<td>inert gas used in clinical applications</td>
		</tr>
		<tr>
			<td>VialMix dental amalgamator</td>
			<td>Bristol-Myers Squibb</td>
			<td>N/A</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>1 MHz, 13mm, unfocused transducer</td>
			<td>Olympus</td>
			<td>A303S-SU</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>20 MHz Function/Arbitrary Waveform Generator</td>
			<td>Agilent</td>
			<td>33220A</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Power Amplifier</td>
			<td>Krohn-Hite Co.</td>
			<td>Model 7500</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Hydrophone</td>
			<td>Bruel and Kjaer</td>
			<td>Type 1803</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Charge Amplifier</td>
			<td>Bruel and Kjaer</td>
			<td>Type 2634</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>500 MHz Oscilloscope</td>
			<td>LeCroy</td>
			<td>9354L</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>VisualSonics&#x2019; Vevo 2100 Imaging System with 34 MHz transducer</td>
			<td>VisualSonics</td>
			<td>2100</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>27G one inch tail vein catheters</td>
			<td>VisualSonics</td>
			<td>N/A</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Genie Plus infusion pump</td>
			<td>Kent Scientific</td>
			<td>GENIE</td>
			<td>&nbsp;</td>
		</tr>
	</tbody>
</table>

introduction to the ultrasound targeted microbubble destruction technique

Gibi negatif yüklü ilgi bir gen kodlayan plazmid DNA vektörleri UTMD, biyoaktif moleküllerin lipid mikrokabarcık kontrast ajanlar 7-9 katyonik kabukları eklenir. Farelerde bu vektör taşıyan mikro kabarcık kalbin sol ventrikül intravenöz veya doğrudan uygulanabilir. Büyük hayvanlarda onlar da intrakoroner bir kateter aracılığıyla infüze olabilir. Dolaşımdan bir hedef organ sonraki teslim mikro kabarcık rezonans frekansta akustik kavitasyon oluşur. Bu mekanik enerji, ya da hedef bölgedeki 10 mikrovasküler endotel hücreleri arasındaki geçici gözenek oluşumuna mikrokabarcık imha sonuçları tarafından üretilen olası görünüyor . Bu sonoporation etkinin bir sonucu olarak, gelişmiş ve endotel hücreleri arasında transfeksiyon verimliliği ve transgen kodlama vektörler çevreleyen doku içine yatırılır. Nükleazlar-sonicated olmayan dokulara daha teslim olasılığını azaltır ve oldukça belirli bir hedef organ transfeksiyon yol açar, kan dolaşımını kalan plazmid DNA hızla düşer.

Watch this Scientific Journal Video about Introduction to the Ultrasound Targeted Microbubble Destruction Technique at JoVE.com

Introduction to the Ultrasound Targeted Microbubble Destruction Technique

Ultrason Hedeflenen Mikro Destruction (UTMD), ultrason ile kalp ve karaciğer gibi organlar, hedef, terapötik genler de dahil olmak üzere, biyoaktif moleküllerin siteye özgü teslimat, doğrudan kullanılabilir<sup&gt; 1-6</sup&gt;.

Ultrason Hedeflenen Mikro İmha Tekniği Giriş

In UTMD, bioactive molecules, such as negatively charged plasmid DNA vectors encoding a gene of interest, are added to the cationic shells of lipid ...

introduction-to-ultrasound-targeted-microbubble-destruction

Research

JoVE Journal

Bioengineering

15.4K Görüntüleme.  University of Hawaii. Ultrason Hedeflenen Mikro Destruction (UTMD), ultrason ile kalp ve karaciğer gibi organlar, hedef, terapötik genler de dahil olmak üzere, biyoaktif moleküllerin siteye özgü teslimat, doğrudan kullanılabilir 1-6.

Video: Introduction to the Ultrasound Targeted Microbubble Destruction Technique

Contrast Ultrasound Targeted Treatment of Gliomas in Mice via Drug-Bearing Nanoparticle Delivery and Microvascular Ablation

We are developing minimally-invasive contrast agent microbubble based therapeutic approaches in which the permeabilization and/or ablation of the microvasculature are controlled by varying ultrasound pulsing parameters.  Specifically, we are testing whether such approaches may be used to treat malignant brain tumors through drug delivery and microvascular ablation.  Preliminary studies have been performed to determine whether targeted drug-bearing nanoparticle delivery can be facilitated by the ultrasound mediated destruction of "composite" delivery agents comprised of 100nm poly(lactide-co-glycolide) (PLAGA) nanoparticles that are adhered to albumin shelled microbubbles. We denote these agents as microbubble-nanoparticle composite agents (MNCAs). When targeted to subcutaneous C6 gliomas with ultrasound, we observed an immediate 4.6-fold increase in nanoparticle delivery in MNCA treated tumors over tumors treated with microbubbles co-administered with nanoparticles and a 8.5 fold increase over non-treated tumors. Furthermore, in many cancer applications, we believe it may be desirable to perform targeted drug delivery in conjunction with ablation of the tumor microcirculation, which will lead to tumor hypoxia and apoptosis. To this end, we have tested the efficacy of non-theramal cavitation-induced microvascular ablation, showing that this approach elicits tumor perfusion reduction, apoptosis, significant growth inhibition, and necrosis. Taken together, these results indicate that our ultrasound-targeted approach has the potential to increase therapeutic efficiency by creating tumor necrosis through microvascular ablation and/or simultaneously enhancing the drug payload in gliomas.

Insonation of microbubbles is a promising strategy for tumor ablation at reduced time-averaged acoustic powers, as well as for the targeted delivery of therapeutics. The purpose of the present study is to develop low duty cycle ultrasound pulsing strategies and nanocarriers to maximize non-thermal microvascular ablation and payload delivery to subcutaneous C6 gliomas.

Kontrast Ultrason Gliomlar, Tedavi Hedeflenen İlaç-Rulman Nanopartikül Teslimat ve Mikrovasküler Ablasyon ile Fare

We are developing minimally-invasive contrast agent microbubble based therapeutic approaches in which the permeabilization and/or ablation of the ...

Biyomühendislik

Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic valve leaflets are composed of interstitial cells suspended within an extracellular matrix (ECM) and are lined with an endothelial cell monolayer. The valve withstands a harsh, dynamic environment and is constantly exposed to shear, flexion, tension, and compression. Research has shown calcific lesions in diseased valves occur in areas of high mechanical stress as a result of endothelial disruption or interstitial matrix damage1-3. Hence, it is not surprising that epidemiological studies have shown high blood pressure to be a leading risk factor in the onset of aortic valve disease4. 
The only treatment option currently available for valve disease is surgical replacement of the diseased valve with a bioprosthetic or mechanical valve5. Improved understanding of valve biology in response to physical stresses would help elucidate the mechanisms of valve pathogenesis. In turn, this could help in the development of non-invasive therapies such as pharmaceutical intervention or prevention. Several bioreactors have been previously developed to study the mechanobiology of native or engineered heart valves6-9. Pulsatile bioreactors have also been developed to study a range of tissues including cartilage10, bone11 and bladder12. The aim of this work was to develop a cyclic pressure system that could be used to elucidate the biological response of aortic valve leaflets to increased pressure loads. 
The system consisted of an acrylic chamber in which to place samples and produce cyclic pressure, viton diaphragm solenoid valves to control the timing of the pressure cycle, and a computer to control electrical devices. The pressure was monitored using a pressure transducer, and the signal was conditioned using a load cell conditioner. A LabVIEW program regulated the pressure using an analog device to pump compressed air into the system at the appropriate rate. The system mimicked the dynamic transvalvular pressure levels associated with the aortic valve; a saw tooth wave produced a gradual increase in pressure, typical of the transvalvular pressure gradient that is present across the valve during diastole, followed by a sharp pressure drop depicting valve opening in systole. The LabVIEW program allowed users to control the magnitude and frequency of cyclic pressure. The system was able to subject tissue samples to physiological and pathological pressure conditions. This device can be used to increase our understanding of how heart valves respond to changes in the local mechanical environment.

Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves

A cyclic pressure bioreactor capable of subjecting heart valve tissue to physiological and pathological pressure conditions has been designed. A LabVIEW program allows users to control pressure magnitude, amplitude and frequency. This device can be used to study the mechanobiology of heart valve tissue or isolated cells.

Devirli Basınç Biyoreaktör Tasarım Ex vivo</emAort Kalp Vanalar> Eğitim

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic ...

Analysis of Targeted Viral Protein Nanoparticles Delivered to HER2+ Tumors

The HER2+ tumor-targeted nanoparticle, HerDox, exhibits tumor-preferential accumulation and tumor-growth ablation in an animal model of HER2+ cancer. HerDox is formed by non-covalent self-assembly of a tumor targeted cell penetration protein with the chemotherapy agent, doxorubicin, via a small nucleic acid linker. A combination of electrophilic, intercalation, and oligomerization interactions facilitate self-assembly into round 10-20 nm particles. HerDox exhibits stability in blood as well as in extended storage at different temperatures. Systemic delivery of HerDox in tumor-bearing mice results in tumor-cell death with no detectable adverse effects to non-tumor tissue, including the heart and liver (which undergo marked damage by untargeted doxorubicin). HER2 elevation facilitates targeting to cells expressing the human epidermal growth factor receptor, hence tumors displaying elevated HER2 levels exhibit greater accumulation of HerDox compared to cells expressing lower levels, both in vitro and in vivo. Fluorescence intensity imaging combined with in situ confocal and spectral analysis has allowed us to verify in vivo tumor targeting and tumor cell penetration of HerDox after systemic delivery. Here we detail our methods for assessing tumor targeting via multimode imaging after systemic delivery.

This article details the procedures for optical imaging analysis of the tumor-targeted nanoparticle, HerDox. In particular, detailed use of the multimode imaging device for detecting tumor targeting and assessing tumor penetration is described here.

Hedefli Viral Protein analizi HER2 + tümörler için teslim Nanopartiküller

The HER2+ tumor-targeted nanoparticle, HerDox, exhibits tumor-preferential accumulation and tumor-growth ablation in an animal model of HER2+ cancer. ...

Manufacture of Concentrated, Lipid-based Oxygen Microbubble Emulsions by High Shear Homogenization and Serial Concentration

Gas-filled microbubbles have been developed as ultrasound contrast and drug delivery agents. Microbubbles can be produced by processing surfactants using sonication, mechanical agitation, microfluidic devices, or homogenization. Recently, lipid-based oxygen microbubbles (LOMs) have been designed to deliver oxygen intravenously during medical emergencies, reversing life-threatening hypoxemia, and preventing subsequent organ injury, cardiac arrest, and death. We present methods for scaled-up production of highly oxygenated microbubbles using a closed-loop high-shear homogenizer. The process can produce 2 L of concentrated LOMs (90% by volume) in 90 min. Resulting bubbles have a mean diameter of ~2 &#956;m, and a rheologic profile consistent with that of blood when diluted to 60 volume %. This technique produces LOMs in high capacity and with high oxygen purity, suggesting that this technique may be useful for translational research labs.

We describe methods for the manufacture of large volumes of lipid-based oxygen microbubbles (LOMs) designed for intravenous oxygen delivery using high-shear homogenization and serial concentration.

Yüksek homojenizasyon ve Seri Konsantrasyon konsantre, Lipid-tabanlı Oksijen Mikro Emülsiyonlar imalatı

Gas-filled microbubbles have been developed as ultrasound contrast and drug delivery agents. Microbubbles can be produced by processing surfactants using ...

A Microfluidic Technique to Probe Cell Deformability

Here we detail the design, fabrication, and use of a microfluidic device to evaluate the deformability of a large number of individual cells in an efficient manner. Typically, data for ~102 cells can be acquired within a 1 hr experiment. An automated image analysis program enables efficient post-experiment analysis of image data, enabling processing to be complete within a few hours. Our device geometry is unique in that cells must deform through a series of micron-scale constrictions, thereby enabling the initial deformation and time-dependent relaxation of individual cells to be assayed. The applicability of this method to human promyelocytic leukemia (HL-60) cells is demonstrated. Driving cells to deform through micron-scale constrictions using pressure-driven flow, we observe that human promyelocytic (HL-60) cells momentarily occlude the first constriction for a median time of 9.3 msec before passaging more quickly through the subsequent constrictions with a median transit time of 4.0 msec per constriction. By contrast, all-trans retinoic acid-treated (neutrophil-type) HL-60 cells occlude the first constriction for only 4.3 msec before passaging through the subsequent constrictions with a median transit time of 3.3 msec. This method can provide insight into the viscoelastic nature of cells, and ultimately reveal the molecular origins of this behavior.

We demonstrate a microfluidics-based assay to measure the timescale for cells to transit through a sequence of micron-scale constrictions.

Mikroakışkan Tekniği Hücre deformabilitesi Probe

Here we detail the design, fabrication, and use of a microfluidic device to evaluate the deformability of a large number of individual cells in an ...

A Microfluidic Chip for ICPMS Sample Introduction

This protocol discusses the fabrication and usage of a disposable low cost microfluidic chip as sample introduction system for inductively coupled plasma mass spectrometry (ICPMS). The chip produces monodisperse aqueous sample droplets in perfluorohexane (PFH). Size and frequency of the aqueous droplets can be varied in the range of 40 to 60 &#181;m and from 90 to 7,000&#160;Hz, respectively. The droplets are ejected from the chip with a second flow of PFH and remain intact during the ejection. A custom-built desolvation system removes the PFH and transports the droplets into the ICPMS. Here, very stable signals with a narrow intensity distribution can be measured, showing the monodispersity of the droplets. We show that the introduction system can be used to quantitatively determine iron in single bovine red blood cells. In the future, the capabilities of the introduction device can easily be extended by the integration of additional microfluidic modules.

We present a discrete droplet sample introduction system for inductively coupled plasma mass spectrometry (ICPMS). It is based on a cheap and disposable microfluidic chip that generates highly monodisperse droplets in a size range of 40&#8722;60 &#181;m at frequencies from 90 to 7,000 Hz.

ICPMS Numune Giriş için mikroakışkan Chip

This protocol discusses the fabrication and usage of a disposable low cost microfluidic chip as sample introduction system for inductively coupled plasma ...

Synthesis of Gold Nanoparticle Integrated Photo-responsive Liposomes and Measurement of Their Microbubble Cavitation upon Pulse Laser Excitation

Photo-responsive nanoparticles (NPs) have received considerable attention because of their potential in providing spatial, temporal, and dosage control over the drug release. However, most of the relevant technologies are still in the development process and are unprocurable by clinics. Here, we describe a facile fabrication of these photo-responsive NPs with commercially available gold NPs and thermo-responsive liposomes. Calcein is used as a model drug to evaluate the encapsulation efficiency and the release kinetic profile upon heat/light stimulation. Finally, we show that this photo-triggered release is due to the membrane disruption caused by microbubble cavitation, which can be measured with hydrophone.

This protocol describes a simple preparation method for gold nanoparticle integrated photo-responsive liposomes with the commercially available materials. It also shows how to measure the microbubble cavitation process of the synthesized liposomes upon the treatment of pulsed laser.

Darbe Lazer Tahrik olma üzerine Altın Nanopartikül Entegre Fotoğraf duyarlı lipozomlar ve Bunların Mikro-kabarcık Kavitasyon Ölçülmesi Sentezi

Photo-responsive nanoparticles (NPs) have received considerable attention because of their potential in providing spatial, temporal, and dosage control ...

An Experimental Protocol for Assessing the Performance of New Ultrasound Probes Based on CMUT Technology in Application to Brain Imaging

The possibility to perform an early and repeatable assessment of imaging performance is fundamental in the design and development process of new ultrasound (US) probes. Particularly, a more realistic analysis with application-specific imaging targets can be extremely valuable to assess the expected performance of US probes in their potential clinical field of application.
The experimental protocol presented in this work was purposely designed to provide an application-specific assessment procedure for newly-developed US probe prototypes based on Capacitive Micromachined Ultrasonic Transducer (CMUT) technology in relation to brain imaging.
The protocol combines the use of a bovine brain fixed in formalin as the imaging target, which ensures both realism and repeatability of the described procedures, and of neuronavigation techniques borrowed from neurosurgery. The US probe is in fact connected to a motion tracking system which acquires position data and enables the superposition of US images to reference Magnetic Resonance (MR) images of the brain. This provides a means for human experts to perform a visual qualitative assessment of the US probe imaging performance and to compare acquisitions made with different probes. Moreover, the protocol relies on the use of a complete and open research and development system for US image acquisition, i.e. the Ultrasound Advanced Open Platform (ULA-OP) scanner.
The manuscript describes in detail the instruments and procedures involved in the protocol, in particular for&#160;the calibration, image acquisition and registration of US and MR images. The obtained results prove the effectiveness of the overall protocol presented, which is entirely open (within the limits of the instrumentation involved), repeatable, and covers the entire set of acquisition and processing activities for US images.

The development of new ultrasound (US) probes based on Capacitive Micromachined Ultrasonic Transducer (CMUT) technology requires an early realistic assessment of imaging capabilities. We describe a repeatable experimental protocol for US image acquisition and comparison with magnetic resonance images, using an ex vivo bovine brain as an imaging target.

Beyin görüntüleme uygulamaya CMUT teknolojisi tabanlı yeni ultrason probları performansını değerlendirmek için deneysel bir iletişim kuralı

The possibility to perform an early and repeatable assessment of imaging performance is fundamental in the design and development process of new ...

Comprehensive Evaluation of the Effectiveness and Safety of Placenta-Targeted Drug Delivery Using Three Complementary Methods

No effective treatments currently exist for placenta-associated pregnancy complications, and developing strategies for the targeted delivery of drugs to the placenta while minimizing fetal and maternal side effects remains challenging. Targeted nanoparticle carriers provide new opportunities to treat placental disorders. We recently demonstrated that a synthetic placental chondroitin sulfate A binding peptide (plCSA-BP) could be used to guide nanoparticles to deliver drugs to the placenta. In this protocol, we describe in detail a system for assessing the efficiency of drug delivery to the placenta by plCSA-BP that employs three separate methods used in combination: in vivo imaging, high-frequency ultrasound (HFUS), and high-performance liquid chromatography (HPLC). Using in vivo imaging, plCSA-BP-guided nanoparticles were visualized in the placentas of live animals, while HFUS and HPLC demonstrated that plCSA-BP-conjugated nanoparticles efficiently and specifically delivered methotrexate to the placenta. Thus, a combination of these methods can be used as an effective tool for the targeted delivery of drugs to the placenta and development of new treatment strategies for several pregnancy complications.

We describe a system that utilizes three methods to evaluate the safety and effectiveness of placenta-targeted drug delivery: in vivo imaging to monitor nanoparticle accumulation, high-frequency ultrasound to monitor placental and fetal development, and HPLC to quantify drug delivery to tissue.

Kapsamlı değerlendirme etkinliği ve güvenliği üç tamamlayıcı yöntemlerle plasenta hedefli ilaç dağıtım

No effective treatments currently exist for placenta-associated pregnancy complications, and developing strategies for the targeted delivery of drugs to ...

Preparing Protein Producing Synthetic Cells using Cell Free Bacterial Extracts, Liposomes and Emulsion Transfer

The bottom-up assembly approach for construction of synthetic cells is an effective tool for isolating and investigating cellular processes in a cell mimicking environment. Furthermore, the development of cell-free expression systems has demonstrated the ability to reconstitute the protein production, transcription and translation processes (DNA&#8594;RNA&#8594;protein) in a controlled manner, harnessing synthetic biology. Here we describe a protocol for preparing a cell-free expression system, including the production of a potent bacterial lysate and encapsulating this lysate inside cholesterol-rich lipid-based giant unilamellar vesicles (GUVs) (i.e., stable liposomes), to form synthetic cells. The protocol describes the methods for preparing the components of the synthetic cells including the production of active bacterial lysates, followed by a detailed step-by-step preparation of the synthetic cells based on a water-in-oil emulsion transfer method. These facilitate the production of millions of synthetic cells in a simple and affordable manner with a high versatility for producing different types of proteins. The obtained synthetic cells can be used to investigate protein/RNA production and activity in an isolated environment, in directed evolution, and also as a controlled drug delivery platform for on-demand production of therapeutic proteins inside the body.

This protocol describes the method, materials, equipment and steps for bottom-up preparation of RNA and protein producing synthetic cells. The inner aqueous compartment of the synthetic cells contained the S30 bacterial lysate encapsulated within a lipid bilayer (i.e., stable liposomes), using a water-in-oil emulsion transfer method.

Hücre Serbest Bakteriyel Özler, Lipozomlar ve Emülsiyon Transferi Kullanarak Protein Üreten Sentetik Hücreler Hazırlama

The bottom-up assembly approach for construction of synthetic cells is an effective tool for isolating and investigating cellular processes in a cell ...